1. Represents the weighted average share price of an aggregate total of 99,185 shares sold in the price range of $24.05 to $24.22 by the reporting person. The reporting person undertakes to provide upon request by the Commission staff, the issuer or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

2. Reflects shares held by the Willis J. Johnson and Reba J. Johnson Revocable Trust DTD 1/16/1997, of which the reporting person and the reporting person's spouse are trustees.

3. Reflects shares held by the Reba Family Limited Partnership II, of which the reporting person and the reporting person's spouse are the general partners.

4. Represents the weighted average share price of an aggregate total of 74,432 shares sold in the price range of $23.50 to $23.94 by the reporting person. The reporting person undertakes to provide upon request by the Commission staff, the issuer or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

Willis J. Johnson

06/15/2012

** Signature of Reporting Person

Date

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person,
see
Instruction
4
(b)(v).